A small buzz is growing about the unconstitutionality of picking Senator Clinton to become Secretary of State. Unfortunately for the senator, congress voted for a pay raise for the cabinet office, and the constitution expressly forbids a member of the legislative branch from taking the office after they vote on the pay raise.
However, as Blogging Blue points out, there is a precedent for Congress lowering the pay of the office to allow one of its members to serve in the executive branch. The challenge then to the incoming Obama Administration is whether they can afford to have not just one vote on Clinton's confirmation, but two.